code: def expected(self, obj, other):
      return Series(
          np.dot(obj.values, other.values), index=other.columns
      )
  
imports: import numpy
  import pytest
  from pandas import DataFrame, Series
  import pandas._testing
label_desc: Use image node_id 3 for calling the TestSeriesDot obj's underlying member method code with example usage: obj.expected(obj, other) and returns: Series